Detection of hematoporphyrin fluorescence during fiberoptic bronchoscopy to localize early bronchogenic carcinoma.

Photoelectric detection of fluorescence from hematoporphyrin-containing "occult" bronchogenic carcinoma is a potentially useful technique for localizing and delineating such cancers. A method is presented which would enable use of a fluorescence-detection system simultaneously with conventional illumination during flexible bronchofiberscopic examination. Preliminary data suggest that quantities of hematoporphyrin as small as 5 picograms can be detected on the surface of tumors by this method.